Add new Column to table with Reference button

Hi all,
I am creating a new process on window like Product Window , i follow the below steps to add Button to Product window but i failed to see Element which i add on System element field in Window Table and Columns

1- Open Element window and create a new element i just add name and print name to be Sync.
2- Then i move move back to Element list window and i am able to see it.
3- Then i move to window " Table and Column" and select my target Table “M_Product”
4- Then press new to add new Column and when i Zoom in to System element field to Pick my new column " Sync" i can’t find it .

How can i see my new element in this Fields , also i tried same thing on Adempiere and it working fine , did i missed something on Metasfresh